A metal blade, which used to be employed as a cutter blade of grass cutters, might contact and damage a structural object when rotating. Accordingly, cord cutters made of nylon resin monofilament often have been used for safety reasons. The nylon cord is excellent in strength enough to be required for mowing. However the cord might abrade to be scattered or discarded on the ground. The nylon resin that is not naturally degradable to be left almost permanently is not excellent from a viewpoint of environmental protection.
Patent documents 1 and 2 disclose cords made of biodegradable resin. Such naturally degradable cords, which might abrade to be scattered, are excellent from a viewpoint of environmental protection.
However, these cords might snap from the base by shock of mowing. Also, they might deteriorate in mowing performance because of crack on the tip or have very bad abrasion resistance, so that they are not sufficiently practical.